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1.
Abstract: Climate change affects individual organisms by altering development, physiology, behavior, and fitness, and populations by altering genetic and phenotypic composition, vital rates, and dynamics. We sought to clarify how selection, phenotypic plasticity, and demography are linked in the context of climate change. On the basis of theory and results of recent empirical studies of plants and animals, we believe the ecological and evolutionary issues relevant to population persistence as climate changes are the rate, type, magnitude, and spatial pattern of climate‐induced abiotic and biotic change; generation time and life history of the organism; extent and type of phenotypic plasticity; amount and distribution of adaptive genetic variation across space and time; dispersal potential; and size and connectivity of subpopulations. An understanding of limits to plasticity and evolutionary potential across traits, populations, and species and feedbacks between adaptive and demographic responses is lacking. Integrated knowledge of coupled ecological and evolutionary mechanisms will increase understanding of the resilience and probabilities of persistence of populations and species.  相似文献   

2.
根表铁锰膜对不同生育期水稻吸收和转运As的影响   总被引:3,自引:0,他引:3  
采用土壤盆栽试验法,研究不同生育期水稻根表铁锰膜形成及其对As吸收和转运的影响。结果表明,两个水稻品种YD6和NK57均在分蘖期形成的铁锰膜量最多,成熟期形成的铁锰膜量最少。水稻根系和茎叶吸收积累As随着水稻不同品种和不同生育期变化较大,As的吸收和积累与铁锰膜形成存在相关性。与分蘖期相比,YD6和NK57成熟期根系As含量分别减少81.6%和62.1%。孕穗期YD6和NK57茎叶As含量分别比分蘖期减少86.4%和65.5%,比成熟期减少87.8%和67.1%。分蘖期水稻根系和茎叶As含量与DCB-Fe或DCB-Mn浓度均呈显著的负相关关系,而孕穗期水稻根系和茎叶As含量与DCB-Fe浓度呈显著的正相关关系,说明不同生育期铁锰膜对水稻植株吸收和转运As的影响不同。两个水稻品种不同生育期,As均主要富集和分配在根表铁锰膜中,铁锰膜中As的分配比率达62.9%~84.9%。NK57从根表铁锰膜、根系和茎叶向籽粒转运As的能力比YD6强,籽粒中As含量是YD6的2.1倍。结果表明可以通过选育As低积累和低转运的水稻品种,来降低污染地区As对人体健康的威胁。  相似文献   

3.
针对中国植物园稀有濒危植物的保护现状和存在问题进行分析,重点讨论了稀有濒危植物在植物园迁地保护的有效性问题,涉及稀有濒危植物在植物园迁地保护的生长和适应问题、稀有濒危植物在植物园重复栽培问题、稀有濒危植物在植物园迁地保护的有效种群大小问题、科学记录系统和监测中心的建立问题。就稀有濒危植物在植物园迁地保护的可持续发展提出了若干对策与建议:以植物园为基础形成保护的网络系统;加强稀有濒危植物迁地保护规划并突出重点;加强科学记录系统和监测中心的建立;多方筹措资金,加强支持强度;加强人才培训与学术交流。  相似文献   

4.
通过对宁波市居民的家电产品系列问题的随即抽样问卷调查,阐述了宁波家电拥有量、使用寿命、更新原因和速率、居民购买家电和处理废旧家电时环保意识和行为,了解了本地区废旧家电的基本情况以及废旧家电处理的途径,在对调查数据进行分析的基础上,给出了结论和建议。  相似文献   

5.
宝鸡城市街尘、土壤及河流沉积物重金属形态迁移特征   总被引:1,自引:0,他引:1  
在宝鸡城市街尘、土壤及河流沉积物基本理化性质和重金属元素含量分析的基础上,重点研究了重金属元素在街尘、土壤及河流沉积物中的赋存形态和迁移特征.结果表明:在街尘中Cu主要以可氧化态和残余态形式存在,Pb主要以可还原态和可氧化态形式存在,Zn和Cd主要以乙酸可提取态形式存在,Mn、Fe、Co、Ni和Cr主要以残余态形式存在...  相似文献   

6.
High atmospheric PM2.5 concentrations are a major problem associated with air pollution in Beijing due to their frequent occurrence and harmful effects. The construction of greenbelts beginning in 2000 has altered the surface structure of the area between 4th ring road and 6th ring road; wind speed, which strongly influences the atmospheric PM2.5 content, has decreased simultaneously during this period. Here, we estimated the effects of different plant configurations on wind speed and dust retention in Beijing. We recommend configuring rough bushy shrub-grass in the northwest, west, and north; grass and rough bushy shrub-grass in the north, east, and southeast; and rough bushy shrub-grass and arbor-shrub-grass in the southwest and northeast. As vegetation types and planting methods influence the ability of shrub-grass and arbor-shrub-grass to block wind and dust, we recommend increasing planting density and introducing plants with hairy leaves and exuberant foliage.  相似文献   

7.
我国环境化学研究的进展   总被引:4,自引:0,他引:4  
刘静宜  金龙珠 《环境化学》1994,13(5):371-381
本文综合介绍了二十年来我国环境化学研究的发展概况。在环境分析化学方面包括了环境分析监测方法、标准参考物质、环境分析方法、形态分析、采样技术与分析测试仪器化等方面。环境污染化学包括了有关大气、水体和土壤环境中化学问题的研究,着重对大气污染物表征、迁移和转化、化学模式和重金属、有机物的水环境化学、水环境中金属烷基化以及土壤中农药等环境化学研究。有关污染生态效应中的化学集中介绍了硒与地方病环境因素关系有  相似文献   

8.
印楝素及印楝杀虫剂的安全性评价研究进展   总被引:2,自引:0,他引:2  
目前开发的新农药必须具有安全性高、残留低、与环境相容的无公害的农药,从一些植物材料中分离出杀虫活性物质来防治害虫具有较长的历史和优势,从印楝中可以分离出多种对害虫具有活性的化合物如印楝素及等可以有效地控制多种害虫。自印楝素被分离鉴定以来,其广谱而独特的生物活性受到人们的广泛关注,印楝素具有良好的杀虫、拒食、驱虫、昆虫生长调节作用等多种生物活性,在农药、日化等领域都有广泛的应用;由印楝素制备的印楝杀虫制剂对害虫的广谱作用、无残留,可减缓害虫的抗药性,是用于蔬菜、果树、茶叶等作物的理想农药,已成为一种近乎完美的植物源杀虫剂。针对日益严重的农药残留及热点关注的环境安全性等问题,系统总结了印楝素及印楝杀虫剂对人、动物等的毒性及环境安全性评价,将有利于全面评价印楝杀虫剂的安全性及有效地指导印楝杀虫剂开发、生产及推广应用。  相似文献   

9.
Zooplankton biomass can be reliably estimated by a non-destructive method based on the statistical relationship between biovolume and the contents of carbon and nitrogen. Integrated zooplankton biovolume and the corresponding organic C and N contents were analysed in paired fresh and fixed (hexamine-buffered formalin) samples. Sample biovolume was estimated through the integration of individual volumes obtained by semi-automatic image analysis on fixed zooplankton samples. The corresponding C and N contents of paired fresh and preserved zooplankton were analysed with a Carlo-Erba C-H-N Analyser. The method allows simultaneous measurement of integrated and individual numbers and biomass (biovolume, C and N) spectrum. It is non-destructive and allows the minimization of errors and variability attributable to differences in the handling processes of samples and to the presence of particles other than zooplankton, like phytoplankton or detritus particulate matter.  相似文献   

10.
南迦巴瓦峰地区自然变异强烈而频繁,地震、泥石流、崩塌与滑坡、雪害、洪水等自然灾害普遍。探讨了自然灾害的特征和规律、灾害的成因及其对社会经济的影响等问题,认为该地区自然灾害具有连锁性、群发性、突发性和频发性;强烈的新构造运动、高山深谷地貌及温热多雨的气候条件等是该地区灾害发生的最主要自然成因。灾害对该区人民生命财产安全、交通运输、山地农业及森林资源等造成严重影响。  相似文献   

11.
The debate in the literature on the science–practice interface suggests a diversity of opinions on how to link science and practice to improve conservation. Understanding this diversity is key to addressing unequal power relations, avoiding the consideration of only dominant views, and identifying strategies to link science and practice. In turn, linking science and practice should promote conservation decisions that are socially robust and scientifically informed. To identify and describe the viewpoints of scientists and decision makers on how the science–practice interface should work in order to improve conservation decisions, we interviewed Brazilian scientists (ecologists and conservation scientists, n = 11) and decision makers (n = 11). We used Q methodology and asked participants to rank their agreement with 48 statements on how the science–practice interface should work in order to improve conservation decisions. We used principal component analysis to identify shared viewpoints. The predominant viewpoint, shared by scientists and decision makers, was characterized by valuing the integration of scientific and strategic knowledge to address environmental problems. The second viewpoint, held mostly by decision makers, was distinguished by assigning great importance to science in the decision-making process and calling for problem-relevant research. The third viewpoint, shared only by scientists, was characterized by an unwillingness to collaborate and a perception of scientists as producers of knowledge that may help decision makers. Most participants agreed organizations should promote collaboration and that actors and knowledge from both science and practice are relevant. Disagreements concerned specific roles assigned to actors, willingness to collaborate, and organizational and institutional arrangements considered effective to link science and practice. Our results suggest there is ample room for collaborations and that impediments lie mainly in existing organizations and formal institutional arrangements rather than in negative attitudes between scientists and decision makers.  相似文献   

12.
Decades of research and policy interventions on biodiversity have insufficiently addressed the dual issues of biodiversity degradation and social justice. New approaches are therefore needed. We devised a research and action agenda that calls for a collective task of revisiting biodiversity toward the goal of sustaining diverse and just futures for life on Earth. Revisiting biodiversity involves critically reflecting on past and present research, policy, and practice concerning biodiversity to inspire creative thinking about the future. The agenda was developed through a 2-year dialogue process that involved close to 300 experts from diverse disciplines and locations. This process was informed by social science insights that show biodiversity research and action is underpinned by choices about how problems are conceptualized. Recognizing knowledge, action, and ethics as inseparable, we synthesized a set of principles that help navigate the task of revisiting biodiversity. The agenda articulates 4 thematic areas for future research. First, researchers need to revisit biodiversity narratives by challenging conceptualizations that exclude diversity and entrench the separation of humans, cultures, economies, and societies from nature. Second, researchers should focus on the relationships between the Anthropocene, biodiversity, and culture by considering humanity and biodiversity as tied together in specific contexts. Third, researchers should focus on nature and economies by better accounting for the interacting structures of economic and financial systems as core drivers of biodiversity loss. Finally, researchers should enable transformative biodiversity research and action by reconfiguring relationships between human and nonhuman communities in and through science, policy, and practice. Revisiting biodiversity necessitates a renewed focus on dialogue among biodiversity communities and beyond that critically reflects on the past to channel research and action toward fostering just and diverse futures for human and nonhuman life on Earth.  相似文献   

13.
Partsch S  Milcu A  Scheu S 《Ecology》2006,87(10):2548-2558
Decomposer invertebrates influence soil structure and nutrient mineralization as well as the activity and composition of the microbial community in soil and therefore likely affect plant performance and plant competition. We established model grassland communities in a greenhouse to study the interrelationship between two different functional groups of decomposer invertebrates, Lumbricidae and Collembola, and their effect on plant performance and plant nitrogen uptake in a plant diversity gradient. Common plant species of Central European Arrhenatherion grasslands were transplanted into microcosms with numbers of plant species varying from one to eight and plant functional groups varying from one to four. Separate and combined treatments with earthworms and collembolans were set up. Microcosms contained 15N labeled litter to track N fluxes into plant shoots. Presence of decomposers strongly increased total plant and plant shoot biomass. Root biomass decreased in the presence of collembolans and even more in the presence of earthworms. However, it increased when both animal groups were present. Also, presence of decomposers increased total N concentration and 15N enrichment of grasses, legumes, and small herbs. Small herbs were at a maximum in the combined treatment with earthworms and collembolans. The impact of earthworms and collembolans on plant performance strongly varied with plant functional group identity and plant species diversity and was modified when both decomposers were present. Both decomposer groups generally increased aboveground plant productivity through effects on litter decomposition and nutrient mineralization leading to an increased plant nutrient acquisition. The non-uniform effects of earthworms and collembolans suggest that functional diversity of soil decomposer animals matters and that the interactions between soil animal functional groups affect the structure of plant communities.  相似文献   

14.
Abstract: Our knowledge of cryptogam taxonomy and species distributions is currently too poor to directly plan for their conservation. We used inventory data from four distinct vegetation types, near Hobart Tasmania, to address the proposition that vegetation type, vascular plant taxon composition, and environmental variables can act as surrogates for mosses and macrofungi in reservation planning. The four vegetation types proved distinct in their taxon composition for all macrofungi, mosses, and vascular plants. We tested the strength of the relationships between the composition of cryptogam taxonomic groups and vascular plant composition and between the environmental variables and canopy cover. Taxon composition of woody vascular plants and vascular plants was the best predictor of the taxon composition of mosses and macrofungi. Combinations of environmental variables and canopy cover were also strong predictors of the taxon composition of mosses and macrofungi. We used an optimization routine for vascular plant taxa and woody plant species and determined the representation of cryptogam taxa in these selections. We identified sites with approximately 10% and 30% of the greatest proportions of vascular plants and woody vascular plants and calculated representation of mosses and macrofungi at these sites. We compared the results of these site selections with random site selections and random selections stratified by vegetation type. Random selection of sites by vegetation type generally captured more cryptogams than site selection by vascular plants at the 10% level. Vascular plant and woody plant taxon composition, vegetation type, and environmental and structural characteristics, all showed promise as surrogates for capturing common cryptogams in reserve systems.  相似文献   

15.
为了解不同浓度铜(Cu)、锌(Zn)重金属污染土壤对乔木抗氧化指标的影响以及为植物修复蠡河重金属污染岸带提供理论依据,选取广玉兰(Magnoliagrandiflora)、香樟(Cinnamomumcamphora)、榉树(Zelkovaschneideriana)幼苗,采用土培法浇灌重金属溶液模拟土壤污染环境,研究不同浓度重金属Cu/Zn对乔木脯氨酸含量、过氧化物酶活性、过氧化氢酶活性及丙二醛含量的单一及复合影响。实验表明,单一Cu胁迫对广玉兰、香樟和榉树的毒害作用较单一,Zn胁迫严重;Cu/Zn复合作用下,3种乔木抗氧化指标均在Cu15和Zn110时达到最大值,表现出较强的抗性,而后随着复合作用强度增加,重金属对其毒害作用增大;75μg/gCu和210μg/gZn单一及复合胁迫时,广玉兰丙二醛含量相对香樟和榉树较接近对照值,过氧化物酶和过氧化氢酶活性较大,脯氨酸含量差别不大。综合分析,不同乔木在不同浓度重金属胁迫下抗氧化指标作出不同响应,广玉兰对高浓度Cu/Zn胁迫不敏感,承受能力和抗性较强,适合于修复Cu/Zn污染较严重土壤。  相似文献   

16.
Monitoring and Evaluation in Conservation: a Review of Trends and Approaches   总被引:12,自引:0,他引:12  
Abstract:  There is growing recognition among conservation practitioners and scholars that good project management is integrally linked to well-designed monitoring and evaluation systems. Most conservation organizations have attempted to develop and implement monitoring and evaluation systems, often with mixed results. One problem seems to be that organizations are trying to build their systems from scratch, overlooking lessons learned from the many efforts to develop useful and practical monitoring and evaluation approaches. Thus, we undertook a review of monitoring and evaluation approaches in conservation and other fields including international development, public health, family planning, education, social services, and business. Here, we present our results for the field of conservation. We categorized the considerable variety of monitoring and evaluation approaches into four broad purposes: basic research; accounting and certification; status assessment; and effectiveness measurement. We focus here on status assessment and effectiveness measurement. Specific lessons that emerged follow: different monitoring and evaluation needs require different approaches; conceptual similarities are widespread among prevailing approaches; inconsistent language impedes communication; confusion among monitoring and evaluation components hinders practitioner ability to choose the appropriate component; and monitoring only quantitative biological variables is insufficient. We suggest that the conservation community continue support of collaborative initiatives to improve monitoring and evaluation, establish clear definitions of commonly used terms, clarify monitoring and evaluation system components, apply available approaches appropriately, and include qualitative and social variables in monitoring efforts.  相似文献   

17.
李其林  黄昀  王萍  刘丰祎 《生态环境》2012,21(4):764-769
采用野外采样和室内分析,试验结果表明三峡库区土壤中重金属Cu、Zn、Pb、Cd、Fe、Cr的变异系数小于50%,重金属的含量比较稳定。稻谷(Oryza sativa)中Cu、Zn、Pb、Cd、Fe、Mn、Cr,玉米(Zea mays)中Pb、Cd、Fe、Mn、Cr和小麦(Triticum aestivum)中Cu、Pb、Cd、Fe、Mn、Cr的变异系数大于50%。土壤、稻谷、玉米、小麦中大部分重金属呈偏态分布。土壤中重金属间均为正相关,且极显著正相关性明显。稻谷、玉米、小麦中重金属间有正相关,也有负相关,但正相关明显多于负相关;稻谷、玉米、小麦中Mn同其它重金属间均有显著正相关性,协同作用明显。稻谷、玉米、小麦中Pb、Cd、Cr的样本超标率较大,污染明显,并且稻谷中Cd与土壤中Cd有直线关系。  相似文献   

18.
土壤动物群落生态学与土壤微生态环境的关系   总被引:3,自引:0,他引:3  
主要综述了国内外蚯蚓种群、捕食性线虫、蚂蚁、跳虫、螨类等土壤动物与土壤理化性质的关系,以及蚯蚓、白蚁、蜗牛、线虫等土壤动物与土壤酶活性的相关性研究;提出了该学科今后的研究趋势。该学科未来要融合土壤动物和整个农林生态系统的研究为一体,把农林的土壤动物群落生态学及其与土壤微生态环境关系结合起来,耦合土壤动物与植物根系-根际微生态环境,链接农林土壤动物与土壤健康及其害虫生态调控,分析探究它们内在的联系和机制,加强立地调控措施,为森林健康和土壤健康提供科学基础资料。  相似文献   

19.
上海佘山国家森林公园空气负离子动态及其主要影响因子   总被引:2,自引:0,他引:2  
以上海佘山国家森林公园为研究地,通过定点观测,对比分析了林内与空地的空气负离子在日变化和季节变化上的规律。研究结果表明:在一日内的上午、中午、下午3个时段,林内与空地的空气负离子浓度和安培空气离子评价系数(CI)值均无显著性差异;而在这3个时段,林内的空气负离子浓度和CI值均显著高于空地;季节上,林内与空地的负离子浓度、CI值以及空气清洁程度均为夏秋季大于春季大于冬季,林内和空地在夏秋两季负离子浓度和CI值都显著大于空地。同时林内的空气清洁程度在4个季节皆高于空地。通过多元回归分析得出,总悬浮颗粒物(TSP)是影响夏秋两季林内负离子浓度和CI值的主要影响因素;相对湿度是影响夏秋两季空地空气负离子浓度和CI值的主要影响因素。  相似文献   

20.
The background, concept, connotation, principles, and methods of eco-planning for an Eco-Demonstration Park (EDP) and sustainability were examined based on a case study of the Luhua EDP in the Chongming Island of Shanghai, China, which is an important part of Shanghai Eco-city planning and construction in the 21st century. By analyzing natural, social and economic conditions, calculating population using the land capacity eco-model, eco-function zoning, and eco-construction, an innovative eco-industrial structure and technical chain were formulated. A comprehensive eco-planning scheme for the EDP was proposed, including planning and management strategies for subsystems of efficient industry, good quality human settlement, high standard eco-construction and eco-tourism as well as effective environmental protection and attractive landscape. The EDP should be an area with coordinated and sustainable economic, social and environmental subsystems. Eco-planning for the EDP should be a very important part of eco-city planning and sustainability. The paper aims to set up a theoretical framework and practical basis for eco-planning and promoting harmony between human and nature.  相似文献   

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